Integrated circuit and method to secure RFID tag, RFID tags are used in credit cards, transaction cards and security access badges, securing the data stored on the RFID chip is of the utmost importance. To date credit cards, transaction cards, security access badges, passports, and other card forms of ID cards are available with RFID tag technology, however RFID tag technology is currently plagued with security risks. The main problem with RFID technology applications is securing of the RFID tag information (data) stored on the chip which can be read anytime the card passed near a RFID reader terminal, making RFID technology highly insecure and prone to being easily hacked and the card information being stolen.
Furthermore, the RFID information can be read at long distances without the card holder's knowledge, even when the user has the card secured in a wallet or handbag. Methods have been taken by manufacturers to issue shielding sleeves for RFID credit cards, transaction cards and security access cards as a safe guard to block the RF signal. However, most individuals loose the sleeve or find it too inconvenient to return the card to the shielding sleeve to secure the RFID tag based card.
The present invention discloses a circuit and method to secure RFID tag data. The present invention allowing (data) stored on the RFID chip to only be read when the card holder activates the RFID circuit by deflecting or bending a piezo element. The present invention does not allow the RFID reader terminal access to the RFID chip information until the card holder bends or deflects the piezo which is retained by the RFID tag or card material. Bending or deflecting the piezo electric element will release energy measurable in volts of energy, energizing the “gate” of a JFET, MOSFET or similar component of the transistor family. Basic operation of a JFET is an electronic switch capable of “on” “off” conditions or often referred to as a closed or open circuit condition. In a JFET or MOSFET electric current flows from one connection, called the source, to a second connection, called the drain, when current flows this is a (closed/short circuit condition) effect of switching “on” the transistor state. A third connection the gate, determines how much current flows.
By applying an increasing positive (for a p-channel JFET) bias voltage at the gate, the current flow from source to drain is impeded by pinching off the channel, in effect switching “off” the transistor (open circuit condition) between the source and the drain. The present invention uses the JFET circuit with the JFET output leads referred to as a “source” and “drain” connected across the RFID antenna with no voltage applied to the “gate” closed circuit condition is created effectively applying a short circuit across the antenna of the RFID tag which does not allow the antenna to be charged by a RFID tag reader, effectively shorting out the antenna. A piezo element when bent or deflected energizes the “gate” input of the JFET switching the JFET current flow which is no longer present (open circuit condition) at the “drain” to “source” connections of the JFET. The RFID antenna, when the JFET is switched, will then be capable of being operating normally and is capable of being energized a by the RFID reader, at which time the RFID chip will transfer the information wirelessly to the RFID reader terminal. This method of applying a short circuit to the two antenna inputs on the RFID chip can be used on both active and passive RFID technologies and secure the RFID tag data from being read.